CN113602326A - Train control method of passive trace - Google Patents
Train control method of passive trace Download PDFInfo
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- CN113602326A CN113602326A CN202110641515.XA CN202110641515A CN113602326A CN 113602326 A CN113602326 A CN 113602326A CN 202110641515 A CN202110641515 A CN 202110641515A CN 113602326 A CN113602326 A CN 113602326A
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B61—RAILWAYS
- B61L—GUIDING RAILWAY TRAFFIC; ENSURING THE SAFETY OF RAILWAY TRAFFIC
- B61L27/00—Central railway traffic control systems; Trackside control; Communication systems specially adapted therefor
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B61—RAILWAYS
- B61L—GUIDING RAILWAY TRAFFIC; ENSURING THE SAFETY OF RAILWAY TRAFFIC
- B61L23/00—Control, warning, or like safety means along the route or between vehicles or vehicle trains
Abstract
The invention relates to a train control method of passive traces, which provides a configurable communication device for realizing continuous communication in a preceding train identification process scene and improving a preceding train and following train control process on the basis of keeping the existing principle of charging a passive transponder by using an electromagnetic induction principle and on the basis of the principle of using a train as a unique core energy source. Compared with the prior art, the method has the advantages of realizing the recognition capability of the approaching scene of the front vehicle and the rear vehicle, providing continuous communication capability in the period, and the like.
Description
Technical Field
The invention relates to a train control method, in particular to a train control method of passive traces.
Background
In the operation process of a large-scale railway train, a train control system is an indispensable part of ground equipment of the train, for example, a CTCS-2-level train control system has the basic principle that a block zone where a train in front is located is detected through a track circuit, so that a track circuit code sequence of a rear section is determined, and the train determines the running speed of the train according to the track circuit code sequence and line information received from a transponder;
or taking the CTCS-3 level as an example, a wireless network including a trackside base station and a core network needs to be built by itself to provide a bidirectional communication channel for a vehicle, and an energy supply and a line cable need to be arranged on the core, so that the energy supply and equipment maintenance problems exist in the same way, and the wireless network is not suitable for the application in the region with rare people, which is the second situation.
In view of the first situation, chinese patent publication No. CN109878555A (application No. 2019100812933) proposes a train control method based on a passive transponder, which provides a train control method that uses a passive transponder to discontinuously advance train operation information, and gets rid of a train control method that sets active devices along a track. Because the problem of active equipment along the track is solved, the passive transponder has limited communication capacity as a non-continuous carrier, cannot identify the approach process of a rear vehicle, can only predict and track with the worst disadvantage, and can only run in an area covered by the method for offline running. Aiming at the situation in the prior art and combining the second situation, how to better adapt to the application in the region with rare human smoke, the operation safety of the whole system is improved, the efficiency is obviously improved, and the technical problem to be solved is solved.
Disclosure of Invention
The invention aims to overcome the defects of the prior art and provide a train control method of a passive trace.
The purpose of the invention can be realized by the following technical scheme:
according to one aspect of the invention, a passive trace train control method is provided, which provides a configurable communication device for realizing continuous communication in a preceding train identification process scene and improving a preceding train and following train control process on the basis of keeping the principle that a passive transponder is charged by utilizing an electromagnetic induction principle and on the basis of the principle that a train is used as a unique core energy source.
As a preferred technical scheme, the method specifically comprises the following steps:
101, starting a train to complete self-checking, entering an initialization completion state after the state meets a design standard, sending self-report information in a broadcast mode by configuring a communication device, and completing train positioning after passing through a first group of transponders in a guiding mode;
step 102, when a train passes through a passive transponder, charging the passive transponder through the principle of electromagnetic induction, reading data information of the train passing through the passive transponder, calculating the distance Sd of a nearest front braking parking position according to a dynamic model and the running speed of the train and information transmitted by the passive transponder, writing the Sd into the passive transponder, and writing corresponding self report information of the train into the passive transponder;
103, under a non-front and rear vehicle approaching scene, the train regenerates a running curve for controlling the train according to the front closest braking distance Sd and the line information read from the transponder and by combining a dynamic model of the current train and the current running speed;
104, under the scene of front and rear train approaching, the configured communication device broadcasts self report information with fixed transmitting power P0, and trains within the coverage range of the P0 capability can receive and analyze the information packet in one direction;
step 105, after the 'self report information' of the train is analyzed, comparing the position information of the front train based on the passive transponder in the message information, identifying the front train by combining the self report information, completing the process scene that the train approaches the front train, and continuously analyzing the broadcast message of the train;
and step 106, continuously measuring the wireless transmission delay information of the front and rear vehicles by combining the high-strength confidence calculated time tag positions in the train in the 'self report information' of the front vehicle, and using the information in real-time calculation.
As a preferred technical solution, the self-report information Rep in step 101 specifically includes:
as a preferred technical solution, the information transmitted by the passive transponder in step 102 includes line curve, gradient, and fixed speed limit information.
As a preferred technical solution, N configurable communication devices are provided.
As a preferred technical scheme, the specific process of identifying the approaching scene of the front and rear vehicles is as follows:
based on the transmitting power P0, the vehicle N starts to receive the Rep _ N-1 of the front vehicle at a distance of N-1D meters from the front vehicle, the information provided by the responder is used for judging that the vehicle N-1 is the actual front vehicle of the vehicle according to the predefined analytic message, the approaching scene identification of the front vehicle and the rear vehicle is completed, and the scene is kept.
As an optimal technical scheme, the monitoring time is continued, and the actual front and rear vehicle time delay is measured through a plurality of packets of messages to obtain time delay information Td.
In a preferred technical scheme, in an approaching scene, a vehicle N continuously receives Rep information sent by a front vehicle N-1; the actual tracking point is a front vehicle N-1 actual braking safe parking point, wherein the distance of the delay Td of the vehicle N needs to be considered and deducted; because the Rep of the front vehicle contains a traction braking state, the actual vehicle control considers the relationship between the speed difference of the two vehicles and the actual distance, wherein the transmission delay Td is obtained in real time.
As a preferable technical scheme, for an N +1 vehicle, N-1 vehicle related information and line data information can be additionally obtained, wherein the N-1 vehicle related information and the line data information comprise traction braking state information of the N-1 vehicle; due to the relay of the N cars, the delay time of the N-1 car should take into account the overlap and the N car processing delay.
As a preferable technical scheme, when the distance between the trains is larger than D or the broadcast message is invalid due to environmental factors, the trains are separated from the scene that the front and rear trains approach, and the train operation is controlled by using the information of the front train recorded in the transponder.
Compared with the prior art, the invention has the following advantages:
1) the invention realizes the recognition capability of the approaching scene of the front and rear vehicles by configuring the communication device, and provides continuous communication capability in the period;
2) the invention realizes wireless transmission monitoring in the scene of approaching the front and rear vehicles and is applied to the safety control algorithm of the front and rear vehicles, improves the calculation of the safety tracking point in the existing algorithm, improves the system efficiency on the premise of ensuring the safety from the least unfavorable point to the confidence calculation safety point (including the real-time property of transmission delay), and provides the possibility of synchronous operation and control, wherein the maximum operation efficiency is close to the physical linkage;
3) the communication device and the safety computer provided by the invention can provide the technology of interconnection and intercommunication by preloading the train control programs of corresponding levels so as to realize global train operation.
Drawings
FIG. 1 is a flow chart embodying the present invention;
fig. 2 is a schematic diagram of an embodiment of the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, not all, embodiments of the present invention. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, shall fall within the scope of protection of the present invention.
Compared with the 2019100812933 patent, the invention has the core improvement: recognizing the process that the rear vehicle approaches the front vehicle, providing a train control improvement method based on an online wireless channel measurement technology, realizing the forward movement of a dangerous control point, improving the operation safety of the whole system and obviously improving the efficiency; a special scene continuous communication means under a communication base station without a line side rail is provided, and the energy of a core train control system provided by the method is continued to be from a train, so that the method is better suitable for being applied in a region with little smoke; the communication device configured in the method can be combined with the corresponding level of train control technology under a small amount of improvement to realize interconnection with the existing line and realize the global operation capability of the equipped train.
The invention provides a configurable communication device on the principle of keeping the existing passive transponder charging principle by utilizing the electromagnetic induction principle and taking a vehicle as a unique core energy source, realizes continuous communication in the scene of the front vehicle identification process, and improves the control algorithm of the front vehicle and the rear vehicle; and provides interconnection and intercommunication possibilities and global operational capabilities.
The train control improvement method is additionally provided with a configuration type communication device based on reliability calculation, and provides communication channel capacity including active sending, unidirectional receiving or real-time bidirectional communication. The existing frame structure design is improved, and the time tag position of high-intensity confidence calculation is added for identifying the approaching scene. The details are as follows (step 2019100812933 is not included):
the reliability requirements are identified and corresponding communication devices (N) are configured according to the specific project requirements, and active transmission and unidirectional reception are taken as examples in the following.
1) The train starting machine completes self-checking, enters an initialization completion state after the state meets the design standard, sends self-report information Rep (table 1) in a broadcast mode by configuring a communication device, and completes train positioning after passing through a first group of transponders (groups) in a guide mode.
TABLE 1
2) When the train passes by the passive transponder, the transponder is charged by the principle of electromagnetic induction, and the data information of the last passing train stored in the transponder is read. Meanwhile, the distance Sd of the nearest front braking parking position is calculated according to the dynamic model and the running speed of the train and the information of the line curve, the gradient, the fixed speed limit and the like transmitted by the passive transponder, the Sd is written into the transponder, and the corresponding report information of the train is written into the transponder.
3) Under the non-front and rear vehicle approaching scene, the train regenerates an operation curve for controlling the train according to the front closest braking distance Sd and the line information read from the transponder and by combining the dynamic model and the current operation speed of the current train.
In consideration of the worst case, when the speed of the front vehicle passes through the passive transponder B1, the speed is 0, the braking distance that the front vehicle writes into the passive transponder 1 is Sd equal to 0, the rear vehicle is the train with the worst line braking performance, the braking distance is Smax, and the rear vehicle needs to start braking at a position, which is far from the passive transponder 1, behind the line running direction Smax to ensure safety.
To be interconnected during the arrangement of the passive transponders, the passive transponders 1 are successively passed behind the line according to the parking position S1 written by the train to passive transponders at a distance of at least Smax and the distance is increased according to the distance between two passive transponders.
4) Under the scene of approaching front and rear trains, the configured communication device (N frequency divisions) broadcasts self-report information (encrypted according to the safety check strength) at fixed transmission power P0, and all train equipment on the line can receive and analyze the information packet in one direction within the coverage range of P0 capability.
5) After the 'self report information' of the train is analyzed, the position information of the front train based on the transponder in the message information is compared, the front train is identified by combining the self report information, the process scene that the train approaches the front train is completed, and the broadcast message of the train is continuously analyzed.
6) And continuously measuring the wireless transmission delay information of the front and rear vehicles by combining the high-strength confidence calculated time tag position in the train in the 'self report information' of the front vehicle, and using the information in real-time calculation. The schematic diagram is shown in fig. 2, and briefly described as follows:
i. in the non-front and rear vehicle approach scene, the vehicle N tracks the danger at the point B according to the method 2019100812933, namely the tail position (including the safety margin) of the worst parking vehicle after the N-1 vehicle passes through the transponder (group) 2;
based on the transmitting power P0, the vehicle N starts to receive a front vehicle Rep _ N-1 at a distance D (P0) m from the vehicle N-1, the information provided by a responder is used for judging that the vehicle N-1 is the actual front vehicle according to predefined analysis information, and the approaching scene identification of the front vehicle and the rear vehicle is completed and the scene is kept;
continuing monitoring time, and measuring actual front and rear vehicle delay through a plurality of packets of messages to obtain delay information Td;
in the approach scene, the host vehicle (N) continuously receives Rep information sent by the preceding vehicle (N-1), see table 1. The actual tracking is point a, i.e., the leading vehicle (N-1) actually brakes the safe stopping point, wherein the host vehicle N needs to give a deduction in consideration of the distance of the delay time Td. Because the Rep (serial number 8) of the front vehicle contains a traction braking state, the actual vehicle control considers the relationship between the vehicle speed difference and the actual distance, wherein the transmission delay Td is obtained in real time. Thus, at this point the front and rear vehicle tracking efficiency approaches the physical coupling efficiency-Td efficiency loss (Td delay effect)
v. for the N +1 vehicle, repeating the steps ii-iv, additionally obtaining the related information of the N-1 vehicle and the line data information, wherein the vehicle control data is more sufficient, and the important is the traction braking state information of the N-1 vehicle. Due to the relay of the N cars, the delay time of the N-1 car should take into account the overlap and the N car processing delay. The automobile brake tail lamp is similar to a front automobile observed in daily driving and is used for pre-judging the operation of the automobile in advance.
And vi, when the distance between the trains is greater than D (P0) or the broadcast message is invalid (cannot be received or cannot be analyzed) due to environmental factors, separating the trains from the front and rear approaching scenes. And entering a basic passive trace train control strategy, and controlling the train to run by using the front train information recorded in the transponder.
7) In the section of communicating with the existing train control system, the security control program of the corresponding CTCS (China train control system), such as CTCS3, installed in the security calculation host of the train control method is preloaded and activated through a specially set transponder, and the communication establishment with the RBC call is completed through the configured communication devices (N). The train runs through a CTCS-3 level train control system to realize global train running.
In order to meet the requirement of global train operation, the train may need to be configured and installed with corresponding hardware equipment according to the characteristics of corresponding interconnection and intercommunication areas.
While the invention has been described with reference to specific embodiments, the invention is not limited thereto, and various equivalent modifications and substitutions can be easily made by those skilled in the art within the technical scope of the invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.
Claims (10)
1. A train control method of passive traces is characterized in that on the basis of keeping the existing principle of utilizing an electromagnetic induction principle to charge a passive transponder, a configurable communication device is provided on the basis of the principle that a train is used as a unique core energy source, and is used for realizing continuous communication in the scene of a front train identification process and improving the control process of the front train and the rear train.
2. The method for controlling a train of passive traces according to claim 1, characterized in that it comprises the following steps:
101, starting a train to complete self-checking, entering an initialization completion state after the state meets a design standard, sending self-report information in a broadcast mode by configuring a communication device, and completing train positioning after passing through a first group of transponders in a guiding mode;
step 102, when a train passes through a passive transponder, charging the passive transponder through the principle of electromagnetic induction, reading data information of the train passing through the passive transponder, calculating the distance Sd of a nearest front braking parking position according to a dynamic model and the running speed of the train and information transmitted by the passive transponder, writing the Sd into the passive transponder, and writing corresponding self report information of the train into the passive transponder;
103, under a non-front and rear vehicle approaching scene, the train regenerates a running curve for controlling the train according to the front closest braking distance Sd and the line information read from the transponder and by combining a dynamic model of the current train and the current running speed;
104, under the scene of front and rear train approaching, the configured communication device broadcasts self report information with fixed transmitting power P0, and trains within the coverage range of the P0 capability can receive and analyze the information packet in one direction;
step 105, after the 'self report information' of the train is analyzed, comparing the position information of the front train based on the passive transponder in the message information, identifying the front train by combining the self report information, completing the process scene that the train approaches the front train, and continuously analyzing the broadcast message of the train;
and step 106, continuously measuring the wireless transmission delay information of the front and rear vehicles by combining the high-strength confidence calculated time tag positions in the train in the 'self report information' of the front vehicle, and using the information in real-time calculation.
3. The method for controlling a train of passive traces according to claim 2, wherein the self-report information Rep in step 101 is specifically:
4. a method as claimed in claim 2, wherein the information transmitted by the passive transponder in step 102 includes information on the route profile, the slope, and the fixed speed limit.
5. A method of passive trail train control according to claim 2, wherein there are N configurable communication devices.
6. The train control method of the passive trace according to claim 2, wherein the specific process of identifying the approaching scene of the front train and the rear train is as follows:
based on the transmitting power P0, the vehicle N starts to receive the Rep _ N-1 of the front vehicle at a distance of N-1D meters from the front vehicle, the information provided by the responder is used for judging that the vehicle N-1 is the actual front vehicle of the vehicle according to the predefined analytic message, the approaching scene identification of the front vehicle and the rear vehicle is completed, and the scene is kept.
7. The method as claimed in claim 2, wherein the monitoring is continued for a duration of time, and the measurement of the actual delay between the front and rear cars is performed by a plurality of packets of messages to obtain the delay information Td.
8. The train control method of the passive trace according to claim 7, wherein in the approaching scene, the host vehicle N continuously receives Rep information sent by the front vehicle N-1; the actual tracking point is a front vehicle N-1 actual braking safe parking point, wherein the distance of the delay Td of the vehicle N needs to be considered and deducted; because the Rep of the front vehicle contains a traction braking state, the actual vehicle control considers the relationship between the speed difference of the two vehicles and the actual distance, wherein the transmission delay Td is obtained in real time.
9. The method of claim 7, wherein for N +1 cars, additionally obtaining N-1 car related information and route data information, including N-1 car traction brake status information; due to the relay of the N cars, the delay time of the N-1 car should take into account the overlap and the N car processing delay.
10. The method as claimed in claim 6, wherein when the distance between the trains is greater than D or the broadcast message is invalid due to environmental factors, the train is controlled to run by using the information of the preceding train recorded in the transponder, and the preceding train is out of the scene of the approach of the preceding train and the following train.
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